Field of the Invention
The present inventions relate generally to earth-boring drill bits having one or more modules or subassemblies attached to the bit body.
Description of the Related Art
U.S. Pat. No. 4,156,123 discloses “Segments of a rock bit are secured together by electron-beam welding. The segments are slightly spaced apart prior to welding by a thin shim of alloying metal such as titanium which improves ductility of the weld and is a strong carbide-former during welding. The shim is positioned between adjacent segments in the region of the crown or dome of the bit. The resulting welded interface is a fine-grain stress-relieved structure with good ductility and resistance to cracking.”
U.S. Pat. No. 4,866,245 discloses “A method is shown for manufacturing rotary rock bits. The method reduces the effect of stresses in the area of the radial weld seams by providing a channel in the interior of the bit which intersects the root region of each weld, providing a generous radius for the root region of each radial weld.”
The inventions disclosed and taught herein are directed to improved methods for attaching drill bit modules or subassemblies to bit bodies to improve the service life thereof.